Answer:
-4(9ab^6)
Step-by-step explanation:
To solve this, you need to multiply the numerator and denominator by the same number to get the new expression.
In the denominator, you would need to multiply ab by 9ab^6 to get 9a^2b^7.
Now, multiply the same thing in the numerator. It would be:
-4(9ab^6)